1. Field of the Invention
The present invention relates to a power connector assembly, and more particularly to an assembly of a receptacle connector and a plug connector interconnecting two separate circuit boards for transmission of power therebetween.
2. The Prior Arts
When designing an electronic circuit, the designer generally will concern two basic parts, i.e., the part of logic (or signal) and the part of power. Because of the current flows through a logic circuit are usually low, the circuit designer needs not to consider the effect of status (for example, temperature) on electrical characteristics (for example, circuit component impedance) when designing a logic circuit. However, the current flows in a power circuit are relatively high which may cause significant change of the electrical characteristics. Therefore, when designing an electronic power connector, the dissipation of heat (due to joule effect) must be taken into account to minimize change of electrical characteristics subject to change of electric current.
Taiwan patent publication No. M319540 discloses a power connector assembly which comprises a receptacle connector adapted to be mounted on one circuit board and a plug connector adapted to be mounted on the other circuit board and mating with the receptacle connector. The receptacle connector comprises an insulative receptacle housing and a plurality of receptacle terminals arrayed in the receptacle housing, and the plug connector comprises an insulative plug housing and a plurality of plug terminals arrayed in the plug housing. Each receptacle terminal and each plug terminal have a main base plate bent and jointed at the top thereof and a pair of mounting arms extending forwardly from one side of the plate. The mounting arms of the plug terminal have a flat-plate shape while the mounting arms of the receptacle terminal have a bending shape. When the plug connector mates with the receptacle connector, the mounting arms of the plug terminal and the mounting arms of the receptacle terminals elastically contact with each other so as to establish an electrical connection. When the power connector assembly is used to transmit high current power, the relatively big area of the main plate of each terminal and the space between two adjacent main plates of each terminal are both favorable to the dissipation of heat generated during transmission of power. Additionally, a plurality of heat-dissipating holes is formed respectively in the top wall of the receptacle housing and the plug housing, which also is favorable to the dissipation of heat.
Although the above-mentioned structure of the power connector assembly is favorable to the dissipation of heat, it still has some shortcomings. Firstly, the heat-dissipate holes are only formed on the top wall of the insulative housing, which will limit the dissipating direction of heat only on one upward direction. Secondly, firmness and solidity of the insulative housing will decrease if too many heat-dissipating holes are formed in the top wall of the housing.
Furthermore, both the receptacle terminal and the plug terminal of the above-mentioned prior art comprises a one piece U-shape main plate made of metallic material. The bending portion of the U-shape plate has a risk of chapping during its manufacturing process, which will influence electrical characteristics of the terminal during power transmission. Moreover, when soldering the terminal to the circuit board, the high temperature of the soldering process will release stress of the bending portion, which will lead to mismatch of the solder legs of the terminal with the solder hole in the circuit board, and will cause failure of the soldering process.
Therefore, it is necessary to develop a new power connector assembly which has improved insulative housings and improved terminals.